Xfce-dusk problem white text

Hi everybody!, i'm new here, and my english is very bad, but i will try;In "Xfce-dusk" theme, some text appears white in a text background white, but if you change this color to a darker color, the others app show a text dark in a background dark. The only solution was i found change the conflictive white color to a gray contrast. In this way, can contrast white background with gray text, and vice versa.

a example of this problem, in facebook page, or google search, when i want write some in the textbox on firefox, the words don't shows. This happens in this theme.